Key West water temperature

Typically about 89° in August — bath-warm.

from the Key West harbor station, about 3 miles away

bath-warm

bath-warm 80° and up perfect 72–79° refreshing 65–71° brisk below 65° 89° typical for August

Smathers Beach water rarely leaves the swimmable range — the question is bath-warm or merely perfect.

The year at a glance

Swimmable year-round.

swimmable 60° 70° 80° 90° 100° 89° 72° JFMAMJJASOND January: typically 72° — perfect February: typically 75° — perfect March: typically 78° — perfect April: typically 80° — bath-warm May: typically 85° — bath-warm June: typically 87° — bath-warm July: typically 89° — bath-warm August: typically 89° — bath-warm September: typically 88° — bath-warm October: typically 83° — bath-warm November: typically 78° — perfect December: typically 74° — perfect

Month by month

Month Typical Feels
January 72° perfect
February 75° perfect
March 78° perfect
April 80° bath-warm
May 85° bath-warm
June 87° bath-warm
July 89° bath-warm
August 89° bath-warm
September 88° bath-warm
October 83° bath-warm
November 78° perfect
December 74° perfect

About this reading

The Key West harbor station sits in the harbor; open-water surf can read a few degrees different.

Reading from the Key West harbor station, about 3 miles away.

Warm water says nothing about surf, rip currents, or bacteria — check local lifeguard flags and advisories.